Data Structure using C- Basics

1. Data structure using C
Dr. Amit J. Chinchawade
PhD ( Electronics & Communication)
Department of Electronics & Computer,
Sharad Institute of Technology College of Engineering , Yadrav

2. C is a procedural programming language known for its simplicity and
flexibility. Its basic structure consists of a set of elements and syntax rules
that we need to follow when writing C programs.

3. 1. Comments:
Comments are used to provide information about the code but are ignored
by the compiler. In C, comments can be single-line comments (starting
with `//`) or multi-line comments (enclosed within `/*` and `*/`).
// This is a single-line comment
/*
This is a
multi-line comment
*/

4. 2. **Preprocessor Directives**:
Preprocessor directives start with a `#` symbol and are used to include
header files, define macros, and perform other preprocessing tasks.
Common directives include `#include` for including header files and
`#define` for defining macros.
#include <stdio.h>
#define PI 3.14159

5. 3. **Main Function**:
Every C program must have a `main` function. Execution of the program
begins with the `main` function.
int main() {
// Your code here
return 0;
}

6. 4. **Data Types**:
C supports various data types such as `int`, `float`, `char`, etc. You use
these to declare variables.
int age;
float price;
char grade;

7. 5. **Variable Declarations**:
Variables are declared before they are used. You specify the data type and
the variable name.
int x, y;

8. 6. **Statements and Expressions**:
C programs consist of statements and expressions that perform actions or
calculations. Statements typically end with a semicolon `;`.
x = 10;
y = x + 5;

9. 7. **Functions**:
You can define your own functions, in addition to `main`, to break the
program into smaller, manageable parts.
int add(int a, int b) {
return a + b;
}

10. 8. **Control Structures**:
C provides control structures such as `if`, `else`, `while`, `for`, etc., to
control the flow of your program.
if (x > 0) {
printf("x is positiven");
} else {
printf("x is non-positiven");
}

11. while (y < 100) {
// Loop body
}
for (int i = 0; i < 5; i++) {
// Loop body
}

12. 9. **I/O Functions**:
C provides functions like `printf` and `scanf` for input and output
operations.
printf("Enter your age: ");
scanf("%d", &age);

13. 10. **Libraries**:
You can use functions from standard libraries by including the appropriate
header files and linking with the necessary libraries.
#include <stdio.h> // Standard I/O library
#include <math.h> // Math library

14. 11. **Return Statement**:
The `main` function typically ends with a `return` statement, indicating the
program's exit status (0 typically means successful execution).
return 0;